Locoweed, the common name of a number of different plants that poison sheep, cattle, and horses on the Great Plains. Some, such as the poison larkspur, are poisonous in themselves. Others are poisonous because they concentrate selenium that exists in the soil. Among these are the milk vetch and white locoweed. The poison affects the nervous system, causing an acute or chronic disorder called loco disease.

Loco is the Spanish word for “mad” or “insane.” The symptoms of loco disease include staggering, falling, defective vision, nausea, constipation, and loss of appetite. Affected animals may suddenly jump for no reason, or run into obstacles. The acute form may end fatally in three days. Animals suffering from the chronic form of the disease may waste away for weeks or even for months.

I think I first heard of locoweed from the old TV series Rawhide. Trail boss Gil Favor and ramrod Rowdy Yates (played by Clint Eastwood long before “Make my day” fame) encountered all kinds of pitfalls and challenges driving the herd from San Antonio TX to Sedalia MO.

Little did I know how common locoweed was and I could have inspected the mysterious plant right in my backyard of Odessa TX. I was probably more interested in having a “cool” name like Rowdy, Sheb or Wishbone instead of plain ole Jimmy.

Be aware of all that you have in your backyard. † en theos ††† jim